Space-based directional observation data system difference resolving method and device

Abstract

The invention discloses a space-based directional observation data system difference resolving method and device. The method comprises the following steps: acquiring a fixed star angular distance measurement data set; the Beidou satellite precise ephemeris obtained from the MGEX system is calculated, and a fixed star angular distance true value set is obtained; calculating an observation data system difference by using the fixed star angular distance measurement data set and the fixed star angular distance true value set; performing error resolving processing on the observation data system difference to obtain system difference characteristics; and performing evaluation processing on the system difference characteristics to obtain system difference precision evaluation information. By using the technical scheme provided by the invention, the influence of different error sources on the space-based directional observation data can be effectively separated and corrected, and the robustness and adaptability of the resolving model are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite navigation, and particularly to a differential solution method and device for space-based directional observation data system. Background Art

[0002] Space-based directional observation, different from traditional navigation systems that rely on ground stations to establish satellite orbit observation and directional observation capabilities, obtains the relative direction information between target satellites and background stars through high-precision star sensors, provides accurate inertial directional references for navigation satellites, thereby reducing the dependence on ground stations, enhancing the independent operation ability of the navigation system, and having the advantages of space autonomy, high-dynamic coverage, and continuous observation.

[0003] Currently, the research on space-based directional observation technology mostly focuses on algorithm verification and data processing, showing preliminary feasibility in the field of supporting the autonomous orbit determination of navigation satellites. However, the research on this technology mainly stays in the simulation verification stage, and has not deeply explored the systematic error problems commonly existing in space-based directional observation data in practical applications. At the level of systematic errors, such as constant bias, linear drift, and periodic errors, are jointly caused by comprehensive factors such as equipment characteristics, environmental changes, and observation conditions, and need to be corrected through effective modeling. Therefore, deeply studying the systematic error characteristics of space-based directional observation data and proposing targeted modeling and solution methods are the keys to realizing the practical application of space-based directional measurement. Summary of the Invention

[0004] Aiming at the typical systematic errors of current space-based directional observation data: constant bias, linear error, and periodic error, the present invention proposes an observation data system error modeling and solution method for the characteristics of these three types of errors. Through in-depth modeling and precise correction of systematic errors, it effectively improves the orbit solution accuracy of navigation satellites, especially showing significant advantages in the estimation of orbital plane orientation parameters, providing a solution for the field of differential solution of observation data system errors, and providing theoretical support and application basis for the further development of future navigation and measurement technologies.

[0005] To achieve the above object, the first aspect of the embodiment of the present invention discloses a differential solution method for space-based directional observation data system errors, and the method includes:

[0006] S1. Obtain a set of stellar angular distance measurement data; the stellar angular distance measurement data includes the relative right ascension observation value and the relative declination observation value between the observed satellite and the target satellite; the observed satellite is a Beidou IGSO satellite, and the target satellite is a Beidou MEO satellite; the set of stellar angular distance measurement data includes the relative right ascension observation value and the relative declination observation value with an observation duration of not less than 24 hours;

[0007] S2. Calculate and process the precise ephemeris of Beidou satellites to obtain the true set of stellar angular distances; the true stellar angular distances include the true relative right ascension and the true relative declination; the precise ephemeris of Beidou satellites is obtained from the MGEX system;

[0008] S3. Process the set of stellar angular distance measurement data and the set of true stellar angular distances to obtain the systematic error of the observation data;

[0009] S4. Perform error resolution processing on the systematic error of the observation data to obtain the characteristics of the systematic error; the characteristics of the systematic error include constant characteristics, linear characteristics, and periodic characteristics;

[0010] S5. Perform evaluation processing on the characteristics of the systematic error to obtain the systematic error accuracy evaluation information.

[0011] As an optional implementation manner, in the first aspect of the embodiments of the present invention, the obtaining of the set of stellar angular distance measurement data includes:

[0012] S11. Construct a staring link between the observing satellite and the observed satellite; the observing satellite includes 3 Beidou IGSO satellites; the observed satellites include 28 MEO satellites, which are distributed in 3 orbital planes, and each orbit corresponds to 3 Beidou IGSO satellites respectively; each Beidou IGSO satellite establishes a fixed observation link with 1 visible MEO satellite on the observed orbit, and when the visible MEO satellite is not visible, switch to other visible MEO satellites in the same orbital plane;

[0013] S12. Continuously observe using Beidou IGSO satellites at a preset observation interval within a preset observation duration to obtain the set of stellar angular distance measurement data; each observation data includes 3 pieces of stellar angular distance measurement data, and each Beidou IGSO satellite obtains 1 piece of stellar angular distance measurement data; optionally, the preset observation duration is not less than 1 day, and the preset observation interval is 15 minutes.

[0014] As an optional implementation manner, in the first aspect of the embodiments of the present invention, the calculating and processing of the precise ephemeris of Beidou satellites to obtain the set of true stellar angular distances includes:

[0015] S21. Obtain the precise ephemeris of Beidou satellites from the MGEX system; the precise ephemeris of Beidou satellites corresponds to the observation time of the set of stellar angular distance measurement data; it should be noted that the precise ephemeris of Beidou satellites obtained from the MGEX system refers to the precise ephemeris of Beidou released by the International Multi-GNSS Experiment (MGEX) Tracking Network, which is public information.

[0016] S22. Use the true stellar angular distance resolution model to process the precise ephemeris of Beidou satellites to obtain the set of true stellar angular distances;

[0017] The true value calculation model expression of the stellar angular distance is as follows:

[0018]

[0019] In the formula, and are the true relative right ascension and the true relative declination between the observed satellite i and the observed satellite j respectively, and are the position vectors of the observed satellite i and the observed satellite j in the inertial coordinate system respectively.

[0020] As an alternative implementation manner, in the first aspect of the embodiments of the present invention, the processing of the stellar angular distance measurement data set and the stellar angular distance true value set to obtain the systematic error of the observation data includes:

[0021] S31. Construct an observable model based on the stellar angular distance measurement data and the stellar angular distance true value;

[0022] The observable model is expressed as:

[0023]

[0024] In the formula, and are the observed relative right ascension and the observed relative declination respectively, and are the true relative right ascension and the true relative declination between the IGSO observed satellite i and the observed MEO satellite j in the celestial coordinate system respectively, and are the relative right ascension error and the relative declination error of the Beidou IGSO satellite i, and are the relative right ascension error and the relative declination error of the Beidou MEO satellite j; both of the above two errors include two parts: systematic error and Gaussian white noise;

[0025] S32. Perform error constraint on the observable model;

[0026] S33. Based on the error constraint, use the observable model to perform calculation processing on the stellar angular distance measurement data set to generate an observation error value; the observation error value includes a constant observation deviation value, a linear observation error value, and a periodic observation error value;

[0027] S34. According to the observation error value, use the observable model to perform calculation on the stellar angular distance measurement data set and the stellar angular distance true value set to obtain the systematic error of the observation data; the systematic error of the observation data includes a relative right ascension systematic error and a relative declination systematic error.

[0028] As an alternative implementation, in the first aspect of the embodiments of the present invention, the error constraint on the observation quantity model is specifically as follows:

[0029] S321. The relative right ascension difference and relative declination difference need to satisfy the following conditions:

[0030]

[0031] In the formula, p represents the satellite number, and N represents the number of Beidou satellites for space-based orientation measurement; and are the relative right ascension error and relative declination error of satellite p; the and have three forms, namely constant deviation, linear error, and periodic error, as specifically described in S322, S323, and S324;

[0032] S322. The constant deviation of the observation quantity model is:

[0033]

[0034] Among them, represents the constant deviation of the relative right ascension of the satellite, represents the constant deviation of the relative declination of the satellite, scid represents the satellite number; JudP(scid) is a parity function judgment, when scid is odd, JudP(scid) is -1, and when scid is even, JudP(scid) is 1; and are the Gaussian white noises with respect to the relative right ascension and relative declination under the constant deviation respectively;

[0035] S323. The linear error of the observation quantity model is:

[0036]

[0037] In the formula, represents the relative right ascension linear error, represents the relative declination linear error, and t is the observation time; and are the Gaussian white noises with respect to the relative right ascension and relative declination under the linear error respectively;

[0038] S324. The periodic error of the observation quantity model is:

[0039]

[0040] In the formula, represents the relative right ascension periodic error, represents the relative declination periodic error, and are Gaussian white noises with respect to the relative right ascension and relative declination under the period deviation respectively.

[0041] As an optional implementation manner, in the first aspect of the embodiments of the present invention, according to the observation error value, using the observation quantity model, resolving the set of stellar angular distance measurement data and the set of true values of stellar angular distance to obtain the systematic error of the observation data;

[0042] S341. Obtain the stellar angular distance measurement data of any observation epoch k from the set of stellar angular distance measurement data

[0043] S342. Obtain the true value of the stellar angular distance corresponding to the any observation epoch k from the set of true values of stellar angular distance;

[0044] S343. Based on the observation quantity model, using the least squares algorithm, calculate the stellar angular distance measurement data and the true value of the stellar angular distance of any observation epoch k to obtain the relative right ascension systematic error of the observed satellite and the observed satellite at the observation epoch k Relative declination systematic error

[0045] S344. Loop to execute steps S341 to S343 to complete the calculation of the relative right ascension systematic error and relative declination systematic error of each satellite corresponding to all observation epochs, and obtain the systematic error of the observation data.

[0046] As an optional implementation manner, in the first aspect of the embodiments of the present invention, the error resolution processing of the systematic error of the observation data to obtain the systematic error characteristics includes:

[0047] S41. Use the constant deviation resolution model to process the systematic error of the observation data to obtain the constant characteristics of each satellite;

[0048] The constant deviation resolution model is expressed as:

[0049]

[0050] In the formula, i represents the satellite number, represents the relative right ascension constant characteristic of satellite i, M represents the number of epochs of the systematic error of the observation data of satellite i collected during the observation period, represents the relative right ascension systematic error of satellite i at the mth epoch; represents the relative declination characteristic of satellite i, represents the relative declination systematic error of satellite i at the mth epoch;

[0051] S42. Using the systematic difference of the observation data, and through least squares fitting calculation by using a preset linear error model of the observed values, obtain the linear characteristics of each satellite;

[0052] The preset linear error model of the observed values is expressed as:

[0053]

[0054] In the formula, i represents the satellite number, represents the relative right ascension linear characteristic of satellite i, represents the relative declination linear characteristic of satellite i, t represents the observation time, a i 、b i 、c i 、d i respectively represent the linear parameters of satellite i;

[0055] S43. Using the systematic difference of the observation data, solve the preset periodic error model of the observed values to obtain the periodic characteristics of each satellite;

[0056] The preset periodic error model of the observed values is expressed as:

[0057]

[0058] In the formula, i represents the satellite number, represents the relative right ascension periodic characteristic of satellite i, represents the relative declination periodic characteristic of satellite i, t represents the observation time, e i 、f i 、g i 、h i respectively represent the period parameters of satellite i;

[0059] As an optional implementation manner, in the first aspect of the embodiments of the present invention, the processing of the systematic difference characteristics to obtain the systematic difference accuracy evaluation information includes:

[0060] S51. Evaluate and process the constant characteristics in the systematic difference characteristics to obtain the solution accuracy of the constant systematic difference. Specifically:

[0061] S511. Based on the systematic difference characteristics, obtain the constant characteristics of satellite i;

[0062] S512. Use the constant deviation evaluation model to evaluate and calculate the constant characteristics of satellite i to obtain the solution accuracy of the constant systematic difference of satellite i; the solution accuracy of the constant systematic difference includes the solution accuracy of the relative right ascension and declination systematic difference and the solution accuracy of the relative declination constant systematic difference;

[0063] The constant deviation evaluation model is expressed as:

[0064]

[0065] Wherein, represents the solution accuracy of the relative equatorial and declination system difference of satellite i, represents the solution accuracy of the relative declination constant system difference of satellite i, represents the relative right ascension constant characteristic of satellite i, represents the relative declination constant characteristic of satellite i, scid represents the satellite number; JudP(scid) is the parity function judgment, when scid is odd, JudP(scid) is -1, when scid is even, JudP(scid) is 1;

[0066] S513. Loop and execute S511 to S512 until the solution accuracy of the constant system difference of all satellites is completed;

[0067] S52. Evaluate and process the linear characteristics in the system difference characteristics to obtain the linear system difference solution accuracy. Specifically:

[0068] S521. Based on the system difference characteristics, obtain the linear parameters of satellite i;

[0069] S522. Use the linear system difference evaluation model to evaluate and calculate the linear parameters of satellite i to obtain the linear system difference solution accuracy of satellite i;

[0070] The linear system difference evaluation model is expressed as:

[0071]

[0072] Wherein, represents the linear system difference solution accuracy of satellite i, a, b, c, d represent the linear parameters of satellite i, scid represents the satellite number; JudP(scid) is the parity function judgment, when scid is odd, JudP(scid) is -1, when scid is even, JudP(scid) is 1;

[0073] S523. Loop and execute S521 to S522 until the linear system difference solution accuracy of all satellites is completed;

[0074] S53. Evaluate and process the periodic characteristics in the system difference characteristics to obtain the periodic system difference solution accuracy. Specifically:

[0075] S531. Based on the system difference characteristics, obtain the periodic parameters of satellite i;

[0076] S532. Use the periodic systematic error evaluation model to evaluate and calculate the periodic parameters of satellite i to obtain the calculation accuracy of the periodic systematic error of satellite i.

[0077] The periodic systematic error evaluation model is expressed as:

[0078]

[0079] In the formula, represents the calculation accuracy of the periodic systematic error of satellite i, e, f, g, h represent the periodic parameters of satellite i, and scid represents the satellite number; JudP(scid) is the parity function judgment. When scid is odd, JudP(scid) is -1, and when scid is even, JudP(scid) is 1.

[0080] S533. Loop and execute S531 - S532 until the calculation accuracy of the periodic systematic error of all satellites is completed.

[0081] S54. Perform comprehensive processing on the calculation accuracy of the constant systematic error, the calculation accuracy of the linear systematic error, and the calculation accuracy of the periodic systematic error to obtain the systematic error accuracy evaluation information.

[0082] The second aspect of the embodiments of the present invention discloses a device for solving the systematic error of space - based directional observation data. The method for solving the systematic error of space - based directional observation data disclosed in the first aspect of the embodiments of the present invention is adopted. The device includes:

[0083] A stellar angular distance measurement data acquisition module, configured to acquire a set of stellar angular distance measurement data; the stellar angular distance measurement data includes the relative right ascension observation value and the relative declination observation value between the observed satellite and the observed target satellite; the observed satellite is a Beidou IGSO satellite, and the observed target satellite is a Beidou MEO satellite.

[0084] A stellar angular distance true value calculation module, configured to perform calculation processing on the precise ephemeris of Beidou satellites to obtain a set of stellar angular distance true values; the stellar angular distance true value includes the relative right ascension true value and the relative declination true value; the precise ephemeris of Beidou satellites is obtained from the MGEX system.

[0085] An observation data systematic error calculation module, configured to process the set of stellar angular distance measurement data and the set of stellar angular distance true values to obtain the observation data systematic error.

[0086] A systematic error characteristic analysis module, configured to perform error calculation processing on the observation data systematic error to obtain systematic error characteristics; the systematic error characteristics include constant characteristics, linear characteristics, and periodic characteristics.

[0087] An evaluation module, configured to perform evaluation processing on the systematic error characteristics to obtain the systematic error accuracy evaluation information.

[0088] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0089] The differential solution method and device for the space-based directional observation data system disclosed in the embodiments of the present invention model and solve the system errors of the space-based directional observation data system with three types of error characteristics, and have the following technical advantages:

[0090] (1) Modeling and solving for multiple types of error characteristics. The present invention incorporates three types of error characteristics, namely constant deviation, linear error, and periodic error, into a unified modeling framework, which can effectively separate and correct the influence of different error sources on the space-based directional observation data, and improve the robustness and adaptability of the solution model.

[0091] (2) Verifying the accuracy by combining with actual simulation data. The technical solution of the present invention is based on the actual on-orbit state of Beidou satellites, and uses the actual simulation system difference as a benchmark for modeling verification to ensure the practical applicability and high-precision reliability of the model. At the same time, through the accuracy evaluation of the observation data system difference, the performance of the solution algorithm is optimized. BRIEF DESCRIPTION OF THE DRAWINGS

[0092] Figure 1 It is a schematic diagram of a differential solution method for a space-based directional observation data system disclosed in an embodiment of the present invention;

[0093] Figure 2 It is a schematic diagram of the data processing process of the space-based directional observation data system difference disclosed in an embodiment of the present invention;

[0094] Figure 3 It is a schematic diagram of the structure of a differential solution device for a space-based directional observation data system disclosed in an embodiment of the present invention;

[0095] Figure 4 It is another schematic diagram of the structure of a differential solution device for a space-based directional observation data system disclosed in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0096] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0097] Embodiment 1

[0098] Please refer to Figure 1 、 2 . Figure 1Schematic diagram of the differential solution method for the space-based directional observation data system disclosed in the embodiments of the present invention Figure 2 Schematic diagram of the differential data processing process for the Beidou satellite observation data system disclosed in the embodiments of the present invention; among them, the differential solution method for the space-based directional observation data system described in this application is applied to a management system, such as a local server or a cloud server for management, etc., which is not limited in the embodiments of the present invention.

[0099] Such as Figure 1 As shown, the differential solution method for the space-based directional observation data system disclosed in the embodiments of the present invention includes:

[0100] S1. Obtain a set of stellar angular distance measurement data; the stellar angular distance measurement data includes the relative right ascension observation value and the relative declination observation value between the observation satellite and the observed satellite; the observation satellite is a Beidou IGSO satellite, and the observed satellite is a Beidou MEO satellite; the set of stellar angular distance measurement data includes the relative right ascension observation value and the relative declination observation value with an observation duration of not less than 24 hours.

[0101] S2. Perform calculation and processing on the precise ephemeris of the Beidou satellite to obtain a set of true values of the stellar angular distance; the true value of the stellar angular distance includes the true value of the relative right ascension and the true value of the relative declination; the precise ephemeris of the Beidou satellite is obtained from the MGEX system.

[0102] S3. Process the set of stellar angular distance measurement data and the set of true values of the stellar angular distance to obtain the system difference of the observation data.

[0103] S4. Perform error solution processing on the system difference of the observation data to obtain the system difference characteristics; the system difference characteristics include constant characteristics, linear characteristics, and periodic characteristics.

[0104] S5. Perform evaluation processing on the system difference characteristics to obtain the system difference accuracy evaluation information.

[0105] In another optional embodiment, the obtaining of the set of stellar angular distance measurement data includes:

[0106] S11. Construct a staring link between the observation satellite and the observed satellite; the observation satellite includes 3 Beidou IGSO satellites; the observed satellites include 28 MEO satellites, which are distributed in 3 orbital planes, and each orbit corresponds to 3 Beidou IGSO satellites respectively; each Beidou IGSO satellite establishes a fixed observation link with 1 visible MEO satellite on the observed orbit, and when the visible MEO satellite is not visible, switch to other visible MEO satellites on the same orbital plane.

[0107] S12. During the preset observation duration, at the preset observation interval, continuously observe using the Beidou IGSO satellites to obtain a set of stellar angular distance measurement data; each observation data includes 3 pieces of stellar angular distance measurement data, and each Beidou IGSO satellite obtains 1 piece of stellar angular distance measurement data; optionally, the preset observation duration is not less than 1 day, and the preset observation interval is 15 minutes.

[0108] In yet another optional embodiment, the calculating and processing the precise ephemeris of Beidou satellites to obtain a set of true values of stellar angular distances includes:

[0109] S21. Obtain the precise ephemeris of Beidou satellites from the MGEX system; the precise ephemeris of Beidou satellites corresponds to the observation time of the set of stellar angular distance measurement data.

[0110] S22. Use the true value calculation model of stellar angular distances to process the precise ephemeris of Beidou satellites to obtain a set of true values of stellar angular distances.

[0111] The expression of the true value calculation model of stellar angular distances is:

[0112]

[0113] In the formula, and are the true relative right ascension and true relative declination between the observed satellite i and the observed satellite j respectively, and are the position vectors of the observed satellite i and the observed satellite j in the inertial coordinate system respectively.

[0114] In yet another optional embodiment, the processing the set of stellar angular distance measurement data and the set of true values of stellar angular distances to obtain the systematic error of the observation data includes:

[0115] S31. Based on the stellar angular distance measurement data and the true values of stellar angular distances, construct an observable model.

[0116] The observable model is expressed as:

[0117]

[0118] In the formula, and are the observed relative right ascension and observed relative declination respectively, and are the true relative right ascension and true relative declination between the IGSO observation satellite i and the observed MEO satellite j in the celestial coordinate system respectively, and are the relative right ascension error and relative declination error of the Beidou IGSO satellite i, and The relative right ascension error and relative declination error of the Beidou MEO satellite j; both of the above two errors include two parts: systematic error and Gaussian white noise;

[0119] S32. Perform error constraint on the observation model;

[0120] S33. Based on the error constraint, use the observation model to perform solution processing on the set of star angular distance measurement data, and generate an observation error value; the observation error value includes a constant observation deviation value, a linear observation error value, and a periodic observation error value;

[0121] S34. According to the observation error value, use the observation model to perform solution on the set of star angular distance measurement data and the set of star angular distance true values, and obtain the systematic error of the observation data; the systematic error of the observation data includes a relative right ascension systematic error and a relative declination systematic error.

[0122] In another optional embodiment, the performing error constraint on the observation model specifically includes:

[0123] S321. The relative right ascension difference and relative declination difference need to satisfy the following conditions:

[0124]

[0125] In the formula, p represents the satellite number, and N represents the number of Beidou satellites for space-based orientation measurement; and are the relative right ascension error and relative declination error of satellite p; the and have three forms, namely constant deviation, linear error, and periodic error, as specifically described in S322, S323, and S324;

[0126] S322. The constant deviation of the observation model is:

[0127]

[0128] Among them, represents the relative right ascension constant deviation of the satellite, represents the relative declination constant deviation of the satellite, scid represents the satellite number; JudP(scid) is a parity function judgment, when scid is odd, JudP(scid) is -1, and when scid is even, JudP(scid) is 1; and are the Gaussian white noises of the relative right ascension and relative declination under the constant deviation respectively;

[0129] S323. The linear error of the observation model is:

[0130]

[0131] Wherein, represents the relative right ascension linear error, and ε δ Linear represents the relative declination linear error, and t is the observation time; and are respectively the Gaussian white noises with respect to the relative right ascension and relative declination under the linear error;

[0132] S324. The periodic error of the observed quantity model is:

[0133]

[0134] Wherein, represents the relative right ascension periodic error, represents the relative declination periodic error, and are respectively the Gaussian white noises with respect to the relative right ascension and relative declination under the period deviation;

[0135] In another optional embodiment, according to the observed error value, using the observed quantity model, the star angular distance measurement data set and the star angular distance true value set are resolved to obtain the observed data systematic error;

[0136] S341. Obtain the star angular distance measurement data of any observation epoch k from the star angular distance measurement data set

[0137] S342. Obtain the star angular distance true value corresponding to the any observation epoch k from the star angular distance true value set;

[0138] S343. Based on the observed quantity model, using the least square algorithm, calculate the star angular distance measurement data and the star angular distance true value of any observation epoch k to obtain the relative right ascension systematic error of the observed satellite and the observed satellite at this observation epoch k relative declination systematic error

[0139] S344. Loop to execute steps S341 to S343 to complete the calculation of the relative right ascension systematic error and relative declination systematic error of each satellite corresponding to all observation epochs, and obtain the observed data systematic error.

[0140] In another optional embodiment, the error resolution process is performed on the observed data systematic error to obtain the systematic error characteristics, including:

[0141] S41. Use the constant deviation calculation model to process the systematic error of the observation data system, and obtain the constant characteristics of each satellite;

[0142] The constant deviation calculation model is expressed as:

[0143]

[0144] In the formula, i represents the satellite number, represents the relative right ascension constant characteristic of satellite i, M represents the number of epochs for collecting the systematic error of the observation data of satellite i within the observation period, represents the relative right ascension systematic error of satellite i at the m-th epoch; represents the relative declination characteristic of satellite i, represents the relative declination systematic error of satellite i at the m-th epoch;

[0145] S42. Use the systematic error of the observation data system and the preset linear error model of the observed values to perform fitting calculation by the least squares method to obtain the linear characteristics of each satellite;

[0146] The preset linear error model of the observed values is expressed as:

[0147]

[0148] In the formula, i represents the satellite number, represents the relative right ascension linear characteristic of satellite i, represents the relative declination linear characteristic of satellite i, t represents the observation time, a i 、b i 、c i 、d i respectively represent the linear parameters of satellite i;

[0149] It should be noted that during the calculation process, the systematic error of the observation data of satellite i within the observation period is used as the observed quantity, and the linear coefficients a, b, c, and d are obtained by fitting with the least squares method;

[0150] S43. Use the systematic error of the observation data system to solve the preset periodic error model of the observed values to obtain the periodic characteristics of each satellite;

[0151] The preset periodic error model of the observed values is expressed as:

[0152]

[0153] In the formula, i represents the satellite number, represents the relative right ascension periodic characteristic of satellite i, represents the relative declination periodic characteristic of satellite i, t represents the observation time, ei , f i , g i , h i respectively represent the period parameters of satellite i;

[0154] It should be noted that during the solution process, the systematic difference of the observation data of satellite i within the observation period is used as the observable quantity, and the period coefficients e, f, g, and h are obtained by least squares fitting.

[0155] In another optional embodiment, the processing of the systematic difference characteristics to obtain the systematic difference accuracy evaluation information includes:

[0156] S51. Evaluate and process the constant characteristics in the systematic difference characteristics to obtain the solution accuracy of the constant systematic difference. Specifically:

[0157] S511. Based on the systematic difference characteristics, obtain the constant characteristics of satellite i;

[0158] S512. Use the constant deviation evaluation model to evaluate and calculate the constant characteristics of satellite i to obtain the solution accuracy of the constant systematic difference of satellite i; the solution accuracy of the constant systematic difference includes the solution accuracy of the relative equatorial coordinate systematic difference and the solution accuracy of the relative declination constant systematic difference;

[0159] The constant deviation evaluation model is expressed as:

[0160]

[0161] In the formula, represents the solution accuracy of the relative equatorial coordinate systematic difference of satellite i, represents the solution accuracy of the relative declination constant systematic difference of satellite i, represents the relative equatorial constant characteristics of satellite i, represents the relative declination constant characteristics of satellite i, scid represents the satellite number; JudP(scid) is the parity function judgment, when scid is odd, JudP(scid) is -1, and when scid is even, JudP(scid) is 1;

[0162] S513. Loop and execute S511 to S512 until the solution accuracy of the constant systematic difference of all satellites is completed;

[0163] S52. Evaluate and process the linear characteristics in the systematic difference characteristics to obtain the solution accuracy of the linear systematic difference. Specifically:

[0164] S521. Based on the systematic difference characteristics, obtain the linear parameters of satellite i;

[0165] S522. Use the linear system error evaluation model to evaluate and calculate the linear parameters of satellite i, and obtain the linear system error calculation accuracy of satellite i;

[0166] The linear system error evaluation model is expressed as:

[0167]

[0168] In the formula, represents the linear system error calculation accuracy of satellite i, a, b, c, and d represent the linear parameters of satellite i, scid represents the satellite number; JudP(scid) is an odd-even function judgment. When scid is odd, JudP(scid) is -1, and when scid is even, JudP(scid) is 1;

[0169] It should be noted that together serve as the relative right ascension linear system error calculation accuracy of satellite i; together serve as the relative declination linear system error calculation accuracy of satellite i.

[0170] S523. Loop and execute S521 - S522 until the linear system error calculation accuracy of all satellites is completed;

[0171] S53. Evaluate and process the periodic characteristics in the system error characteristics to obtain the periodic system error calculation accuracy. Specifically:

[0172] S531. Based on the system error characteristics, obtain the periodic parameters of satellite i;

[0173] S532. Use the periodic system error evaluation model to evaluate and calculate the periodic parameters of satellite i, and obtain the periodic system error calculation accuracy of satellite i;

[0174] The periodic system error evaluation model is expressed as:

[0175]

[0176] In the formula, represents the periodic system error calculation accuracy of satellite i, e, f, g, and h represent the periodic parameters of satellite i, scid represents the satellite number; JudP(scid) is an odd-even function judgment. When scid is odd, JudP(scid) is -1, and when scid is even, JudP(scid) is 1;

[0177] It should be noted that together serve as the relative right ascension periodic system error calculation accuracy of satellite i; together serve as the relative declination periodic system error calculation accuracy of satellite i.

[0178] S533. Execute S531 - S532 in a loop until the periodic systematic difference calculation accuracy for all satellites is completed.

[0179] S54. Perform comprehensive processing on the constant systematic difference calculation accuracy, the linear systematic difference calculation accuracy, and the periodic systematic difference calculation accuracy to obtain systematic difference accuracy evaluation information.

[0180] Embodiment 2

[0181] Please refer to Figure 3 。 Figure 3 This is a schematic structural diagram of a space - based directional observation data systematic difference calculation device disclosed in an embodiment of the present invention. Among them, Figure 3 The described device can be applied to a management system, such as a local server or a cloud server for management, etc., which is not limited in the embodiments of the present invention. As Figure 3 shown, the device may include:

[0182] A stellar angular distance measurement data acquisition module 201, configured to acquire a set of stellar angular distance measurement data; the stellar angular distance measurement data includes the relative right ascension observation value and the relative declination observation value between an observation satellite and an observed satellite; the observation satellite is a Beidou IGSO satellite, and the observed satellite is a Beidou MEO satellite; the set of stellar angular distance measurement data includes the relative right ascension observation value and the relative declination observation value with an observation duration of not less than 12 hours;

[0183] A stellar angular distance true value calculation module 202, configured to perform calculation processing on the precise ephemeris of Beidou satellites to obtain a set of stellar angular distance true values; the stellar angular distance true value includes the relative right ascension true value and the relative declination true value; the precise ephemeris of Beidou satellites is obtained from the MGEX system;

[0184] An observation data systematic difference calculation module 203, configured to process the set of stellar angular distance measurement data and the set of stellar angular distance true values to obtain the observation data systematic difference;

[0185] A systematic difference characteristic analysis module 204, configured to perform error calculation processing on the observation data systematic difference to obtain systematic difference characteristics; the systematic difference characteristics include constant characteristics, linear characteristics, and periodic characteristics;

[0186] An evaluation module 205, configured to perform evaluation processing on the systematic difference characteristics to obtain systematic difference accuracy evaluation information.

[0187] This Embodiment 2 is the product embodiment corresponding to Embodiment 1, and the steps and methods included are the same as those in Embodiment 1, and will not be elaborated in Embodiment 2.

[0188] Embodiment 3

[0189] Please refer toFigure 4 , Figure 4 is a schematic structural diagram of another differential calculation device for a space-based directional observation data system disclosed in an embodiment of the present invention. Among them, Figure 4 the described device can be applied to a management system, such as a local server or a cloud server for management, etc., which is not limited in the embodiments of the present invention. As Figure 4 shown, the device may include:

[0190] a memory 301 storing executable program code;

[0191] a processor 302 coupled to the memory 301;

[0192] The processor 302 calls the executable program code stored in the memory 301 to execute the steps in the differential calculation method of the space-based directional observation data system described in Embodiment 1.

[0193] The device embodiments described above are only illustrative. The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed to multiple network modules. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0194] Through the specific descriptions of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the above technical solutions, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, and the storage medium includes read-only memory (ROM), random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), one-time programmable read-only memory (OTPROM), electrically-erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc memories, magnetic disk memories, tape memories, or any other computer-readable medium that can be used to carry or store data.

[0195] Finally, it should be noted that: The disclosed method and device for differential solution of space-based directional observation data system according to the embodiments of the present invention are only the preferred embodiments of the present invention, and are only used to illustrate the technical solutions of the present invention, rather than to limit them; Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A differential solution method for a space-based directional observation data system, characterized in that, The method includes: S1. Obtain a set of stellar angular distance measurement data; the stellar angular distance measurement data includes the relative right ascension observation value and the relative declination observation value between the observing satellite and the observed satellite; the observing satellite is a Beidou IGSO satellite, and the observed satellite is a Beidou MEO satellite; the set of stellar angular distance measurement data includes the relative right ascension observation value and the relative declination observation value with an observation duration of not less than 24 hours. S2. Perform calculation and processing on the precise ephemeris of Beidou satellites to obtain a set of true values of stellar angular distances; the true values of stellar angular distances include the true value of relative right ascension and the true value of relative declination; the precise ephemeris of Beidou satellites is obtained from the MGEX system. S3. Process the set of stellar angular distance measurement data and the set of true values of stellar angular distances to obtain the systematic error of the observation data. S4. Perform error resolution processing on the systematic error of the observation data to obtain the characteristics of the systematic error; the characteristics of the systematic error include constant characteristics, linear characteristics, and periodic characteristics. S5. Perform evaluation processing on the characteristics of the systematic error to obtain the evaluation information of the systematic error accuracy.

2. The method for differential solution of space-based directional observation data system according to claim 1, characterized in that The obtaining of the set of stellar angular distance measurement data includes: S11. Construct a staring link between the observing satellite and the observed satellite; the observing satellite includes 3 Beidou IGSO satellites; the observed satellites include 28 MEO satellites, which are distributed in 3 orbital planes, and each orbit corresponds to 3 Beidou IGSO satellites respectively; each Beidou IGSO satellite establishes a fixed observation link with 1 visible MEO satellite on the observed orbit, and when the visible MEO satellite is not visible, switch to other visible MEO satellites on the same orbital plane. S12. Continuously perform observations using Beidou IGSO satellites at a preset observation interval within a preset observation duration to obtain a set of stellar angular distance measurement data; each observation data includes 3 pieces of stellar angular distance measurement data, and each Beidou IGSO satellite obtains 1 piece of stellar angular distance measurement data.

3. The differential solution method of the space-based directional observation data system according to claim 1, wherein, The performing of calculation and processing on the precise ephemeris of Beidou satellites to obtain a set of true values of stellar angular distances includes: S21. Obtain the precise ephemeris of Beidou satellites from the MGEX system; the precise ephemeris of Beidou satellites corresponds to the observation time of the set of stellar angular distance measurement data. S22. Use the true value calculation model of stellar angular distances to process the precise ephemeris of Beidou satellites to obtain a set of true values of stellar angular distances. The expression of the true value calculation model of stellar angular distances is: Wherein, and are respectively the true relative right ascension and the true relative declination between the observation satellite i and the observed satellite j, and are respectively the position vectors of the observation satellite i and the observed satellite j in the inertial coordinate system.

4. The method for differential solution of space-based directional observation data system according to claim 1, characterized in that, The processing of the set of stellar angular distance measurement data and the set of true values of stellar angular distances to obtain the systematic error of the observation data includes: S31. Based on the stellar angular distance measurement data and the true values of stellar angular distances, construct an observable model. The observable model is expressed as: In the formula, and are the relative right ascension observation value and the relative declination observation value respectively, and are the true relative right ascension and the true relative declination between the IGSO observation satellite i in the celestial coordinate system and the observed MEO satellite j respectively, and are the relative right ascension error and the relative declination error of the Beidou IGSO satellite i, and are the relative right ascension error and the relative declination error of the Beidou MEO satellite j; both of the above two errors include two parts: systematic error and Gaussian white noise; S32. Perform error constraint on the observable model. S33. Based on the error constraint, use the observable model to perform calculation and processing on the set of stellar angular distance measurement data to generate observation error values; the observation error values include constant observation deviation values, linear observation error values, and periodic observation error values. S34. According to the observed error value, use the observable model to calculate the set of stellar angular distance measurement data and the set of true stellar angular distance values, and obtain the systematic error of the observation data; the systematic error of the observation data includes the relative right ascension systematic error and the relative declination systematic error.

5. The differential solution method of the space-based directional observation data system according to claim 1, characterized in that, Perform error constraint on the observable model. Specifically: S321. The relative right ascension difference and the relative declination difference need to satisfy the following conditions: Wherein, p represents the satellite number, and N represents the number of Beidou satellites for space-based directional measurement; and are the relative right ascension error and relative declination error of satellite p; the and have three forms, namely constant deviation, linear error, and periodic error, as specifically described in S322, S323, and S324; S322. The constant deviation of the observable model is: Among them, represents the deviation of the satellite relative to the right ascension constant, represents the deviation of the satellite relative to the declination constant, and scid represents the satellite number; JudP(scid) is a parity function judgment. When scid is odd, JudP(scid) is -1, and when scid is even, JudP(scid) is 1; and are respectively the Gaussian white noises with respect to the relative right ascension and relative declination under the constant deviation; S323. The linear error of the observable model is: In the formula, represents the relative right ascension linear error, represents the relative declination linear error, and t is the observation time; and are respectively the Gaussian white noises with respect to the relative right ascension and relative declination under the linear error; S324. The periodic error of the observable model is: In the formula, represents the relative right ascension periodic error, represents the relative declination periodic error, and are respectively the Gaussian white noises with respect to the relative right ascension and relative declination under the periodic deviation.

6. The space-based directional observation data system differential solution method according to claim 4, wherein According to the observed error value, use the observable model to calculate the set of stellar angular distance measurement data and the set of true stellar angular distance values, and obtain the systematic error of the observation data, including: S341. Obtain the stellar angular distance measurement data for any observation epoch k from the set of stellar angular distance measurement data S342. Obtain the true stellar angular distance value corresponding to any observation epoch k from the set of true stellar angular distance values. S343. Based on the observation model, the least squares algorithm is used to calculate the measured data of the stellar angular distance and the true value of the stellar angular distance at any observation epoch, and the relative right ascension systematic error between the observed satellite and the observed satellite at the k-th observation epoch is obtained. Relative declination systematic error S344. Loop through steps S341 to S343 to complete the calculation of the relative right ascension systematic error and the relative declination systematic error for each satellite corresponding to all observation epochs, and obtain the systematic error of the observation data.

7. The method for differential solution of space-based directional observation data system according to claim 1, characterized in that Perform error calculation and processing on the systematic error of the observation data to obtain the systematic error characteristics, including: S41. Use the constant deviation calculation model to process the systematic error of the observation data to obtain the constant characteristics of each satellite. The constant deviation calculation model is expressed as: In the formula, \(i\) represents the satellite number, represents the relative right ascension constant characteristic of satellite \(i\), and \(M\) represents the number of epochs for collecting the systematic difference of the observation data of satellite \(i\) within the observation period. represents the relative right ascension systematic difference of satellite \(i\) at the \(m\)-th epoch; represents the relative declination characteristic of satellite \(i\), represents the relative declination systematic difference of satellite \(i\) at the \(m\)-th epoch; S42. Use the systematic error of the observation data to calculate the preset linear error model of the observed value to obtain the linear characteristics of each satellite. The preset linear error model of the observed value is expressed as: In the formula, i represents the satellite number, represents the relative right ascension linear characteristic of satellite i, represents the relative declination linear characteristic of satellite i, t represents the observation time, a i , b i , c i , d i respectively represent the linear parameters of satellite i; S43. Use the systematic error of the observation data to calculate the preset periodic error model of the observed value to obtain the periodic characteristics of each satellite. The preset periodic error model of the observed value is expressed as: In the formula, i represents the satellite number, represents the relative right ascension periodic characteristic of satellite i, represents the relative declination periodic characteristic of satellite i, t represents the observation time, e i 、f i 、g i 、h i respectively represent the period parameters of satellite i.

8. The differential solution method for the space-based directional observation data system according to claim 1, wherein Perform evaluation processing on the systematic error characteristics to obtain systematic error accuracy evaluation information, including: S51. Perform evaluation processing on the constant characteristics in the systematic error characteristics to obtain the calculation accuracy of the constant systematic error. S52. Perform evaluation processing on the linear characteristics in the systematic error characteristics to obtain the calculation accuracy of the linear systematic error. S53. Perform evaluation processing on the periodic characteristics in the systematic error characteristics to obtain the calculation accuracy of the periodic systematic error.

9. A differential calculation device for a space-based directional observation data system, characterized in that, The device includes: A stellar angular distance measurement data acquisition module, configured to acquire a set of stellar angular distance measurement data; the stellar angular distance measurement data includes the relative right ascension observed value and the relative declination observed value between the observed satellite and the observed satellite; the observed satellite is a Beidou IGSO satellite, and the observed satellite is a Beidou MEO satellite. A true stellar angular distance calculation module, configured to perform calculation processing on the precise ephemeris of Beidou satellites to obtain a set of true stellar angular distance values; the true stellar angular distance includes the true relative right ascension and the true relative declination; the precise ephemeris of Beidou satellites is obtained from the MGEX system. An observation data systematic error calculation module, configured to process the set of stellar angular distance measurement data and the set of true stellar angular distance values to obtain the systematic error of the observation data. The systematic error characteristic analysis module is used to perform error calculation processing on the systematic error of the observation data system to obtain systematic error characteristics; the systematic error characteristics include constant characteristics, linear characteristics, and periodic characteristics; The evaluation module is used to perform evaluation processing on the systematic error characteristics to obtain systematic error accuracy evaluation information.

10. A differential solution device for a space-based directional observation data system, characterized in that, The device includes: A memory storing executable program code; A processor coupled to the memory; The processor calls the executable program code stored in the memory and executes the space-based directional observation data systematic error calculation method according to any one of claims 1-8.

Images